Not sure if this is brag-worthy, but it made me giggle. DD4 is into knock knock jokes at the moment. The other day she was trying to convince me to play with her (princesses - urgh) so she put on her most charming smile and came up with this one:

Knock knock.
Who's there?
Salmon. (pronounced like sammen)
Salmon who?
Salmon want to play with me? (geddit, as in 'someone want to play with me?')

Hahaha, groan.